media: dvb-frontends: tda10048: Fix integer overflow

[ Upstream commit 1aa1329a67cc214c3b7bd2a14d1301a795760b07 ]

state->xtal_hz can be up to 16M, so it can overflow a 32 bit integer
when multiplied by pll_mfactor.

Create a new 64 bit variable to hold the calculations.

Link: https://lore.kernel.org/linux-media/20240429-fix-cocci-v3-25-3c4865f5a4b0@chromium.org


Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 8167e4d7dc086d4f7ca7897dcff3827e4d22c99a)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>